Monsanto, BASF Agree to New Restraints on Controversial Herbicide

Chemical makers Monsanto Co. and BASF SA agreed to new restrictions on the use of a herbicide blamed for damaging millions of acres of U.S. crops this year.

Monsanto and BASF over the past year began marketing new versions of the dicamba weed killer to U.S. soybean and cotton farmers, who for years have struggled to kill weeds that have developed resistance to other commonly used herbicides, like Monsanto's Roundup spray. Monsanto developed new genetically engineered soybean and cotton seeds that were designed to resist dicamba, which would allow farmers to spray it onto growing crops without damaging them.

But farmers and crop researchers say dicamba, historically prone to drifting onto neighboring fields, has proved difficult to control. Scientists who study weeds estimate that dicamba over the summer damaged more than 3 million acres of fields planted with soybeans that weren't engineered to resist the chemical.

The U.S. Environmental Protection Agency on Thursday approved proposals from Monsanto and BASF that would make dicamba a "restricted use pesticide." Those products can only be used by a certified applicator, or someone under direct supervision of a certified applicator.

The companies proposed the change to address "the high number of crop damage incidents reported to EPA since June 2017," according to notices the EPA posted on Friday.

Monsanto and BASF representatives had no immediate comment.

The new limitations on dicamba use fall short of curbs some critics believe are necessary to avoid a repeat of that damage next year, when some projections show spraying of the potent chemical on U.S. farm fields could double.

Write to Jacob Bunge at

(END) Dow Jones Newswires

October 13, 2017 11:09 ET (15:09 GMT)